I see also that when I pin the end segments they stay in their original location rather than glued to the blood vessel. Now to work on some kind of file using both your technique and my original pinning technique using the Formula Node.

I still cannot do what I set out to do which is attach each Astrocyte project including its end foot to the blood vessel wall. I can get it to attach as in my original example file but then there is so much collision intersection of the blood vessel as to make it useless. But I will keep plodding along trying to discover a magical anti-intersection technique.

I'm also trying key framing of the mass at the point where they are in good position to lock the portion I want.

I assume you mean model the complete astrocyte including foot processes, drag the foot processes into each position on the blood vessel, and then use soft body dynamics to prevent intersection?

I'm pretty sketchy with connectors but sounds intriguing.

Excellent thoughts.

Yeah, I was referring to modelling the complete astrocyte, and using dynamics and connectors. Dynamics is like hair, there's a lot to read but i've found connectors can be a little more stable than the hair constraints in the past.

Key framing the "Mass" of the points may get you far enough to actually finish the project, and you can research other avenues when you have more time. Would be interested to see your solution whichever way you choose :)

I love to model cells and such with MoExtrude. I'll use the Connectors on them.

Keyframing the mass is not getting me away from the intersection problem so far but works well.

maliohammad: I will also try a separate Spline Guide plugin spline for each of the 20 foot processes to precisely position them away from the blood vessel to prevent intersection that way. That's a great plugin.

It's pretty interesting how using a combination of Spline Guide plugin and my Xpresso pinning of points to polygons I can pin a point on a hair yet shape the dynamic remainder of the hair. Also a Hair Collider tag helps prevent intersection.

Moving the points of the shaper spline (Spline 0) of the example file allows loads of hair positioning. The free plugin Spline Guide is needed to view the attached file.

And by setting the mass of a point to 0, I can pin that point to the original pre-dynamics position.

So all this allows me precise positioning of cell projections, tentacles, and such.

Finally got the look I wanted. The important thing was to demonstrate the cell appendixes and the End Feet arrangement. Because it is so much easier to align the first points of hair, I made the cylinder the source of the Hair Object and the hairs finally aligned like I wanted. Then with Xpresso I attached the ends to the cell body (sphere). By setting the Hair Gravity to 0 I was able to avoid the Hair Collider tag because all this seems to do is make the splines twitch and jump.

Luckily I did not need to try and pin both the end points (31) and one or two back (29)

And Spline Guide plugin had a little too much personality for me and was really difficult to use for precise hair placing.

Now on to textures and the rest of the scene.

In dealing with this project the things I learned were marvelous: setting the mass of a point to 0 (wow), using Spline Guide plugin (lots of future uses), how to move a point along a direction vector, and the unpredictable results from Hair Collider tag. Thanks again to Southpaw and Maliohammad.

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Glad you made some progress. The only solutions I could find for aligning the hair points to a surface/point normal used Python to set the tangents of the points the spline. At least we've learned some new stuff in process. Thanks for sharing the files. :)